Resource cycles in ecosystems

1
Resource cycles in ecosystems
2
Cycles

• Essential nutrients for living things flow
  through the ecosystem.
• The reservoirs can be in the air, land, or
  oceans.
• Important resources cycle through the living and
  nonliving parts of ecosystems

3
Water cycle
Water moves from the air to land as precipitation
then back up via evaporation transpiration
4
Carbon cycle

• Carbon cycles from atmospheric CO2 into living
  things through photosynthesis
• CO2 returns to atmosphere from respiration
  burning
• Oceans, soils plants act as a carbon reservoirs

5
Nitrogen cycle

• Nitrogen is an essential nutrient for all
  organisms
• It exists in the atmosphere as N2
• It is transformed by bacteria into a form plants
  can use

6
Human impact on natural cycles
Human activity such as burning fossil fuels
deforestation has greatly impacted natural
nutrient cycles, causing air, water, and soil
pollution
7
Review

1. What is the process by which water moves from
   plants into the atmosphere?
2. In what form do plants take in carbon?
3. What type of organism makes atmospheric nitrogen
   usable for other living things?